This proposal for a new Institutional National Research Service Award to Indiana University will support broadly integrative training in the areas of sexual reproduction and development. Training will focus on behavior, largely but not exclusively of animals, and will address key questions in the development and expression of sex differences, and maternal and paternal effects on morphological, sexual, and social development. Indiana University's excellent support for research and its globally recognized strengths in animal behavior, endocrinology, human sexual health, and evolution of development will ensure high quality training. The 17 Program Faculty are drawn from four departments (Biology, Chemistry, Gender Studies, Psychology) and two additional degree-granting programs (Program in Medical Sciences, Program in Neural Science). They are also associated with one or more of six research centers, most importantly, the Center for the Integrative Study of Animal Behavior (CISAB). Support is requested for five years to enable training of four predoctoral and two postdoctoral students. In addition to course work in the fundamentals and intensive research training including required mini-rotations and proposal writing in the first year and structured rotations later in training, pre-doctoral trainees will participate in: (1) a research-based course focused on Concepts in Reproductive Diversity; (2) a second hands-on methods course, Techniques in Reproductive Diversity; and 3) a Research Ethics course, all to be co- taught by the training faculty and enhanced by a CISAB tradition of involving visiting scientists in course offerings. Predoctoral trainees will be drawn from applicants to the degree-granting programs of the Program Faculty. Postdoctoral trainees will be recruited nationally, chosen so as to broaden their skills and perspectives, and expected to foster research collaboration. Intense effort will be devoted to increasing minority recruitment and retention, building on a highly successful undergraduate program devoted to under represented minorities.